Prosecutors have dropped charges against a Newburyport man whose car crossed the Interstate 495 median in Methuen and struck a another vehicle, killing the driver, because the crash was caused by a medical emergency.

Motor vehicle homicide and other charges against 37-year-old Jeffrey Plante in connection with the September 2012 crash were dismissed this week in Lawrence District Court.

Ted Cranney, Plante's attorney, tells The Eagle-Tribune that medical findings in the case showed Plante passed out behind the wheel due to an undiagnosed and "unexpected cardiac episode."

Police say Plante's vehicle crossed from the north to the southbound lanes and crashed into another car, killing 32-year-old Kurt Kelly of Westford.